Question: Simplify the following expression: $x = \dfrac{5z}{8} + \dfrac{z}{5}$
In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $8$ and $5$ $\lcm(8, 5) = 40$ $ x = \dfrac{5}{5} \cdot \dfrac{5z}{8} + \dfrac{8}{8} \cdot \dfrac{z}{5} $ $x = \dfrac{25z}{40} + \dfrac{8z}{40}$ $x = \dfrac{25z +8z}{40}$ $x = \dfrac{33z}{40}$